Was asked to look at a number of fire call points that were failing on test. I found that even if the units were opened up and the glass removed the sprung loaded sider at the top which was meant to drop on breakage of glass (or its lowering by use of the test key) failed to move. Manually exercising the slider vigorously for a bit freed it up and I was able to leave them all passing test.
However 3 out of 6 not working is not good - will the others fail soon?- how long will the freed ones last? I am considering using a little silicon on the sliders after all the dust has been removed.
Any similar experience or thoughts?

They are probably about 7 years old.
Yes - a test or a fire will tell if one is stuck or not - it just depends which occurs first! That's why I was thinking of lubricating them - but was wondering what was best - I thought silicon, but there is always 3in1, WD40, baby oil, butter.....
Quite frankly I am surprised if 3in 6 can stick that there has not been a product recall on them!
I did have some Menvier spares with me and noted that with these the glass pressed directly on micro-switch button so there was no plastic link to stick. However they had a different shaped test key and the client was not too keen to have a mix, nor wanting to change them all unless essential.

Are they surface or flush - I've seen a few of the old bardic points and similar design with the interposing link stick when tightened onto uneven surfaces - Honeywell have control of Chloride now so I wouldn't hold out too much hope of manufacturer support.

Seven tears in, and for just six BGU's I'd be tempted advise the client to swap them out for a better brand of 470 ohm units anyway - perhaps KAC or similar OEM kit might be a good choice

Manufacturer (once I got a non premium rate number for them!) says DON'T lubricate. And I can see their point - I would be taking full responsibility for anything going wrong. Suggested I check for freedom of movement on all of them. That I will do and any that are not really free will be going back.

Are they surface or flush - I've seen a few of the old bardic points and similar design with the interposing link stick when tightened onto uneven surfaces - Honeywell have control of Chloride now so I wouldn't hold out too much hope of manufacturer support.

Surface mounted - so thanks for suggestion - I will check they are not twisted.

Remember that all the call points in an installaiton must be able to be tested with the same key - more that 1 key means it is non-compliant with current eddition of BS5839.

It would also be worth remembering that most smoke detectors have a manufactures life cycle design of 10 years after which they need changing otherwise you could find your insurer refusing to pay a claim as the system was non-compliant. May be worth discussing a planned overhaul/update of all of the system as this would mean the batteries, panel circuit board, detector heads and call points were all brought up to date. Depends how big the system is but buying bits for old systems often attracts a price premium compared to buying a new system plus when you take into account call out fees and having to re-test things after changing bits and pieces over the next few years as all the parts expire this could become and ongoing case of make-do and mend - just a thought.

Originally posted by: Dave69Where are the call points located? Call points in kitchen areas are always a problem

No, none in the kitchen - although I had thought it odd as that might be one of the most likely sources of fire!
I was back there today and retested the call points - all passed test first time including the ones that were previously sticking. The good "work out" seemed to have done the trick without resorting to any lubricant.

If 3 out of 6 points are failing, I think they need replacement; and refer to the manufacturer for suitable components. Don't try and repair, its not your fault, why take on a risk that is not yours?

I agree - was not at all good. Also agree that's it not a good idea to try getting inside or lubricate. So they are being closely monitored and if any stick again I will be recommending their complete replacement.

Strange that when I was at school (OMG - 50 years ago!) no one had any trouble setting the alarms off! Although when there was a fire in the basement of my hall of residence most of the alarms didn't go off - but then they had been tampered with and the torching of the wicker laundry baskets had been arson! all a bit worrying. Although the fire was in a concrete corridor and didn't spread the smoke did, as some of the fire doors had been left open. Folk got trapped in their rooms on higher floors and had to be rescued. After all that excitement I wandered round the back of the block and saw two of the Asian students happily playing Ping-Pong in another part of the basement. My shouting didn't perturb them - but when I climbed down there and pointed through the glass of the internal doors to the firemen in breathing apparatus battling through the smoke, just the far side - that sure did move them fast!

Its a small village hall, basic structure cast concrete although some wooden panelling. But its single story and all the main rooms have at least two exits to outside. None-the-less the call points are being more frequently checked so action can be taken at the first sign of any further sticking. But as I have said, on rechecking yesterday all were working 100% first time.